Acknowledgments

Many people have contributed code included in the Free Software
Foundation's distribution of GNU Emacs. To show our appreciation for
their public spirit, we list here in alphabetical order those who have
written substantial portions. Others too numerous to mention have
reported and fixed bugs, and added features to many parts of Emacs.
We thank them for their generosity as well.

This list is intended to mention every contributor of a major package or
feature we currently distribute; if you know of someone we have omitted,
please make a bug report. More comprehensive information is
available in the ChangeLog files, summarized in the file
etc/AUTHORS in the distribution.

Per Abrahamsen wrote the customization facilities, as well as
double.el, for typing accented characters not normally available
from the keyboard; xt-mouse.el, which allows mouse commands
through Xterm; gnus-cus.el, which implements customization
commands for Gnus; gnus-cite.el, a citation-parsing facility for
news articles; gnus-score.el, scoring for Gnus; cpp.el,
which hides or highlights parts of C programs according to preprocessor
conditionals; and the widget library files wid-browse.el,
wid-edit.el, widget.el. He also co-wrote
gnus-soup.el.

Tomas Abrahamsson wrote artist.el, a package for producing
ASCII art with a mouse or with keyboard keys.

Michael Albinus wrote dbus.el, a package that implements the
D-Bus message bus protocol; zeroconf.el, a mode for browsing
Avahi services; secrets.el, an interface to keyring daemons for
storing confidential data; and filenotify.el and the associated
low-level interface routines, for watching file status changes.
He and Kai Großjohann wrote the Tramp package, which provides
transparent remote file editing using ssh, ftp, and other network
protocols. He and Daniel Pittman wrote tramp-cache.el.

Ralf Angeli wrote scroll-lock.el, a minor mode which keeps the
point vertically fixed by scrolling the window when moving up and down
in the buffer.

Aurélien Aptel added dynamic module support to Emacs. Philipp
Stephani and others also worked on the dynamic module code.

Joe Arceneaux wrote the original text property implementation, and
implemented support for X11.

Miles Bader wrote image-file.el, support code for visiting image
files; minibuf-eldef.el, a minor mode that hides the minibuffer
default value when appropriate; rfn-eshadow.el, shadowing of
read-file-name input; mb-depth.el, display of minibuffer
depth; button.el, the library that implements clickable buttons;
face-remap.el, a package for changing the default face in
individual buffers; and macroexp.el for macro-expansion. He
also worked on an early version of the lexical binding code.

David Bakhash wrote strokes.el, a mode for controlling Emacs by
moving the mouse in particular patterns.

Juanma Barranquero wrote emacs-lock.el (based on the original
version by Tom Wurgler), which makes it harder to exit with valuable
buffers unsaved; and frameset.el, for saving and restoring the
frame/window setup. He also made many other contributions to other
areas, including MS Windows support.

Eli Barzilay wrote calculator.el, a desktop calculator for
Emacs.

Steven L. Baur wrote footnote.el which lets you include
footnotes in email messages; and gnus-audio.el and
earcon.el, which provide sound effects for Gnus. He also wrote
gnus-setup.el.

Scott Bender, Michael Brouwer, Christophe de Dinechin, Carl Edman,
Christian Limpach and Adrian Robert developed and maintained the
NeXTstep port of Emacs.

Stephen Berman wrote todo-mode.el (based on the original version
by Oliver Seidel), a package for maintaining TODO list files.

Anna M. Bigatti wrote cal-html.el, which produces HTML calendars.

Ray Blaak and Simon South wrote opascal.el, a mode for editing
Object Pascal source code.

Martin Blais, Stefan Merten, and David Goodger wrote rst.el, a
mode for editing reStructuredText documents.

Jim Blandy wrote Emacs 19's input system, brought its configuration and
build process up to the GNU coding standards, and contributed to the
frame support and multi-face support. Jim also wrote tvi970.el,
terminal support for the TeleVideo 970 terminals; and co-wrote
wyse50.el (q.v.).

Bob Chassell wrote texnfo-upd.el, texinfo.el, and
makeinfo.el, modes and utilities for working with Texinfo files;
and page-ext.el, commands for extended page handling. He also
wrote the Emacs Lisp introduction. See Top.

Jihyun Cho wrote hanja-util.el and hangul.el, utilities
for Korean Hanja.

Andrew Choi and Yamamoto Mitsuharu wrote the Carbon support, used
prior to Emacs 23 for macOS. Yamamoto Mitsuharu continued to
contribute to macOS support in the newer Nextstep port; and also
improved support for multi-monitor displays.

Chong Yidong was the Emacs co-maintainer from Emacs 23 to 24.3. He made many
improvements to the Emacs display engine. He also wrote
tabulated-list.el, a generic major mode for lists of data;
and improved support for themes and packages.

James Clark wrote SGML mode, a mode for editing SGML documents; and
nXML mode, a mode for editing XML documents. He also contributed to
Emacs's dumping procedures.

Mike Clarkson wrote edt.el, an emulation of DEC's EDT editor.

Glynn Clements provided gamegrid.el and a couple of games that
use it, Snake and Tetris.

Andrew Cohen wrote spam-wash.el, to decode and clean email before
it is analyzed for spam.

Theresa O'Connor wrote json.el, a file for parsing and
generating JSON files.

Georges Brun-Cottan and Stefan Monnier wrote easy-mmode.el, a
package for easy definition of major and minor modes.

Mathias Dahl wrote image-dired.el, a package for viewing image
files as thumbnails.

Julien Danjou wrote an implementation of desktop notifications
(notifications.el, and related packages for ERC and Gnus);
and color.el, a library for general color manipulation.
He also made various contributions to Gnus.

Vivek Dasmohapatra wrote htmlfontify.el, to convert a buffer or
source tree to HTML.

Matthieu Devin wrote delsel.el, a package to make newly-typed
text replace the current selection.

Eric Ding wrote goto-addr.el,

Jan Djärv added support for the GTK+ toolkit and X drag-and-drop.
He also wrote dynamic-setting.el.

Oscar Figueiredo wrote EUDC, the Emacs Unified Directory Client, which
is an interface to directory servers via LDAP, CCSO PH/QI, or BBDB; and
ldap.el, the LDAP client interface.

Fred Fish wrote the support for dumping COFF executable files.

Karl Fogel wrote bookmark.el, which implements named
placeholders; mail-hist.el, a history mechanism for outgoing
mail messages; and saveplace.el, for preserving point's
location in files between editing sessions.

Gary Foster wrote scroll-all.el, a mode for scrolling several buffers
together.

Noah Friedman wrote rlogin.el, an interface to Rlogin,
type-break.el, which reminds you to take periodic breaks from
typing, and eldoc-mode, a mode to show the defined parameters or
the doc string for the Lisp function near point.

Shigeru Fukaya wrote a testsuite for the byte-compiler.

Keith Gabryelski wrote hexl.el, a mode for editing binary files.

Kevin Gallagher rewrote and enhanced the EDT emulation, and wrote
flow-ctrl.el, a package for coping with unsuppressible XON/XOFF
flow control.

Fabián E. Gallina rewrote python.el, the major mode for the
Python programming language used in Emacs 24.3 onwards.

Kevin Gallo added multiple-frame support for Windows NT and wrote
w32-win.el, support functions for the MS-Windows window system.

Howard Gayle wrote much of the C and Lisp code for display tables and
case tables. He also wrote rot13.el, a command to display the
plain-text form of a buffer encoded with the Caesar cipher;
vt100-led.el, a package for controlling the LEDs on
VT100-compatible terminals; and much of the support for ISO-8859
European character sets (which includes iso-ascii.el,
iso-insert.el, iso-swed.el,
iso-syntax.el, iso-transl.el, and swedish.el).

Stephen Gildea made the Emacs quick reference card, and made many
contributions for time-stamp.el, a package for maintaining
last-change time stamps in files.

Julien Gilles wrote gnus-ml.el, a mailing list minor mode for
Gnus.

David Gillespie wrote the Common Lisp compatibility packages;
Calc, an advanced calculator and mathematical tool, since
maintained and developed by Jay Belanger; complete.el, a partial
completion mechanism; and edmacro.el, a package for editing
keyboard macros.

Bob Glickstein wrote sregex.el, a facility for writing regexps
using a Lisp-like syntax.

Boris Goldowsky wrote avoid.el, a package to keep the mouse
cursor out of the way of the text cursor; shadowfile.el, a
package for keeping identical copies of files in more than one place;
format.el, a package for reading and writing files in various
formats; enriched.el, a package for saving text properties in
files; facemenu.el, a package for specifying faces; and
descr-text.el, describing text and character properties.

Michelangelo Grigni wrote ffap.el which visits a file,
taking the file name from the buffer.

Odd Gripenstam wrote dcl-mode.el for editing DCL command files.

Michael Gschwind wrote iso-cvt.el, a package to convert between
the ISO 8859-1 character set and the notations for non-ASCII
characters used by TeX and net tradition.

Bastien Guerry wrote gnus-bookmark.el, bookmark support for Gnus;
as well as helping to maintain Org mode (q.v.).

Henry Guillaume wrote find-file.el, a package to visit files
related to the currently visited file.

Doug Gwyn wrote the portable alloca implementation.

Ken'ichi Handa implemented most of the support for international
character sets, and wrote most of the Emacs 23 font handling code. He
also wrote composite.el, which provides a minor mode that
composes characters automatically when they are displayed;
isearch-x.el, a facility for searching non-ASCII
text; and ps-bdf.el, a BDF font support for printing
non-ASCII text on a PostScript printer. Together with Naoto
Takahashi, he wrote quail.el, an input facility for typing
non-ASCII text from an ASCII keyboard.

Jesper Harder wrote yenc.el, for decoding yenc encoded messages.

Alexandru Harsanyi wrote a library for accessing SOAP web services.

K. Shane Hartman wrote chistory.el and echistory.el,
packages for browsing command history lists; electric.el and
helper.el, which provide an alternative command loop and
appropriate help facilities; emacsbug.el, a package for
reporting Emacs bugs; picture.el, a mode for editing
ASCII pictures; and view.el, a package for perusing
files and buffers without editing them.

John Heidemann wrote mouse-copy.el and mouse-drag.el,
which provide alternative mouse-based editing and scrolling features.

Jon K Hellan wrote utf7.el, support for mail-safe transformation
format of Unicode.

Karl Heuer wrote the original blessmail script, implemented the
intangible text property, and rearranged the structure of the
Lisp_Object type to allow for more data bits.

Manabu Higashida ported Emacs to MS-DOS.

Anders Holst wrote hippie-exp.el, a versatile completion and
expansion package.

Denis Howe wrote browse-url.el, a package for invoking a WWW
browser to display a URL.

Lars Magne Ingebrigtsen did a major redesign of the Gnus news-reader and
wrote many of its parts. Several of these are now general components of
Emacs, including: dns.el for Domain Name Service lookups;
format-spec.el for formatting arbitrary format strings;
netrc.el for parsing of .netrc files; and
time-date.el for general date and time handling.
He also wrote network-stream.el, for opening network processes;
url-queue.el, for controlling parallel downloads of URLs;
and implemented libxml2 support. He also wrote eww.el,
an Emacs Lisp web browser; and implemented native zlib decompression.
Components of Gnus have also been written by: Nagy Andras, David
Blacka, Scott Byer, Ludovic Courtès, Julien Danjou, Kevin Greiner, Kai
Großjohann, Joe Hildebrand, Paul Jarc, Simon Josefsson, Sascha
Lüdecke, David Moore, Jim Radford, Benjamin Rutt, Raymond Scholz,
Thomas Steffen, Reiner Steib, Jan Tatarik, Didier Verna, Ilja Weis,
Katsumi Yamaoka, Teodor Zlatanov, and others (see Contributors).

Andrew Innes contributed extensively to the MS-Windows support.

Seiichiro Inoue improved Emacs's XIM support.

Philip Jackson wrote find-cmd.el, to build a find
command-line.

Ulf Jasper wrote icalendar.el, a package for converting Emacs
diary entries to and from the iCalendar format;
newsticker.el, an RSS and Atom based Newsticker; and
bubbles.el, a puzzle game.

Simon Josefsson wrote dns-mode.el, an editing mode for Domain
Name System master files; dig.el, a Domain Name System interface;
flow-fill.el, a package for interpreting RFC2646 formatted text
in messages; fringe.el, a package for customizing the fringe;
imap.el, an Emacs Lisp library for talking to IMAP servers;
password-cache.el, a password reader; nnimap.el, the IMAP
back-end for Gnus; url-imap.el for the URL library;
rfc2104.el, a hashed message authentication facility; the Gnus
S/MIME and Sieve components; and tls.el and starttls.el
for the Transport Layer Security protocol.

Arne Jørgensen wrote latexenc.el, a package to
automatically guess the correct coding system in LaTeX files.

Alexandre Julliard wrote vc-git.el, support for the Git version
control system.

Tomoji Kagatani implemented smtpmail.el, used for sending out
mail with SMTP.

Ivan Kanis wrote vc-hg.el, support for the Mercurial version
control system.

Henry Kautz wrote bib-mode.el, a mode for maintaining
bibliography databases compatible with refer (the troff
version) and lookbib, and refbib.el, a package to convert
those databases to the format used by the LaTeX text formatting package.

Taichi Kawabata added support for Devanagari script and the Indian
languages, and wrote ucs-normalize.el for Unicode normalization.

Taro Kawagishi implemented the MD4 Message Digest Algorithm in Lisp; and
wrote ntlm.el and sasl-ntlm.el for NT LanManager
authentication support.

Howard Kaye wrote sort.el, commands to sort text in Emacs
buffers.

Michael Kifer wrote ediff, an interactive interface to the
diff, patch, and merge programs; and
Viper, an emulator of the VI editor.

Richard King wrote the first version of userlock.el and
filelock.c, which provide simple support for multiple users
editing the same file. He also wrote the initial version of
uniquify.el, a facility to make buffer names unique by adding
parts of the file's name to the buffer name.

Peter Kleiweg wrote ps-mode.el, a mode for editing PostScript
files and running a PostScript interpreter interactively from within
Emacs.

Daniel LaLiberte wrote edebug.el, a source-level debugger for
Emacs Lisp; cl-specs.el, specifications to help edebug
debug code written using David Gillespie's Common Lisp support; and
isearch.el, Emacs's incremental search minor mode. He also
co-wrote hideif.el (q.v.).

Karl Landstrom and Daniel Colascione wrote js.el, a mode for
editing JavaScript.

Vinicius Jose Latorre wrote the Emacs printing facilities, as well as
ps-print (with Jim Thompson, Jacques Duthen, and Kenichi Handa),
a package for pretty-printing Emacs buffers to PostScript printers;
delim-col.el, a package to arrange text into columns;
ebnf2ps.el, a package that translates EBNF grammar to a syntactic
chart that can be printed to a PostScript printer; and
whitespace.el, a package that detects and cleans up excess
whitespace in a file (building on an earlier version by Rajesh Vaidheeswarran).

Frederic Lepied wrote expand.el, which uses the abbrev
mechanism for inserting programming constructs.

Lars Lindberg wrote msb.el, which provides more flexible menus
for buffer selection; co-wrote imenu.el (q.v.); and rewrote
dabbrev.el, originally written by Don Morrison.

Anders Lindgren wrote autorevert.el, a package for automatically
reverting files visited by Emacs that were changed on disk;
cwarn.el, a package to highlight suspicious C and C++
constructs; and follow.el, a minor mode to synchronize windows
that show the same buffer.

Thomas Link wrote filesets.el, a package for handling sets of
files.

Juri Linkov wrote misearch.el, extending isearch to multi-buffer
searches; the code in files-x.el for handling file- and
directory-local variables; and the info-finder feature that
creates a virtual Info manual of package keywords.

Leo Liu wrote pcmpl-x.el, providing completion for
miscellaneous external tools; and revamped support for Octave in Emacs 24.4.

Károly Lőrentey wrote the multi-terminal code, which allows
Emacs to run on graphical and text terminals simultaneously.

Martin Lorentzon wrote vc-annotate.el, support for version
control annotation.

Dave Love wrote much of the code dealing with Unicode support and
Latin-N unification. He added support for many coding systems,
including the various UTF-7 and UTF-16 coding systems. He also wrote
autoarg-mode, a global minor mode whereby digit keys supply
prefix arguments; autoarg-kp-mode, which redefines the keypad
numeric keys to digit arguments; autoconf.el, a mode for editing
Autoconf files; cfengine.el, a mode for editing Cfengine files;
elide-head.el, a package for eliding boilerplate text from file
headers; hl-line.el, a minor mode for highlighting the line in
the current window on which point is; cap-words.el, a minor mode
for motion in CapitalizedWordIdentifiers; latin1-disp.el, a
package that lets you display ISO 8859 characters on Latin-1 terminals
by setting up appropriate display tables; the version of
python.el used prior to Emacs 24.3; smiley.el, a
facility for displaying smiley faces; sym-comp.el, a library
for performing mode-dependent symbol completion; benchmark.el
for timing code execution; and tool-bar.el, a mode to control
the display of the Emacs tool bar. With Riccardo Murri he wrote
vc-bzr.el, support for the Bazaar version control system.

Eric Ludlam wrote the Speedbar package; checkdoc.el, for checking
doc strings in Emacs Lisp programs; dframe.el, providing
dedicated frame support modes; ezimage.el, a generalized way to
place images over text; chart.el for drawing bar charts etc.; and
the EIEIO (Enhanced Implementation of Emacs Interpreted Objects)
package. He was also the main author of the CEDET (Collection of Emacs
Development Environment Tools) package. Portions were also written by
Jan Moringen, David Ponce, and Joakim Verona.

Roland McGrath wrote compile.el (since updated by Daniel
Pfeiffer), a package for running compilations in a buffer, and then
visiting the locations reported in error messages; etags.el, a
package for jumping to function definitions and searching or replacing
in all the files mentioned in a TAGS file; with Sebastian
Kremer find-dired.el, for using dired commands on output
from the find program; grep.el for running the
grep command; map-ynp.el, a general purpose boolean
question-asker; autoload.el, providing semi-automatic
maintenance of autoload files.

Alan Mackenzie wrote the integrated AWK support in CC Mode, and
maintained CC Mode from Emacs 22 onwards.

Neil M. Mager wrote appt.el, functions to notify users of their
appointments. It finds appointments recorded in the diary files
used by the calendar package.

Ken Manheimer wrote allout.el, a mode for manipulating and
formatting outlines, and icomplete.el, which provides incremental
completion feedback in the minibuffer.

Bill Mann wrote perl-mode.el, a mode for editing Perl code.

Brian Marick and Daniel LaLiberte wrote hideif.el, support for
hiding selected code within C #ifdef clauses.

Simon Marshall wrote regexp-opt.el, which generates a regular
expression from a list of strings; and the fast-lock and lazy-lock
font-lock support modes. He also extended comint.el and
shell.el, originally written by Olin Shivers.

Charlie Martin wrote autoinsert.el, which provides automatic
mode-sensitive insertion of text into new files.

Yukihiro Matsumoto and Nobuyoshi Nakada wrote Ruby-mode.

Tomohiro Matsuyama wrote the native Elisp profiler.

Thomas May wrote blackbox.el, a version of the traditional
blackbox game.

David Megginson wrote derived.el, which allows one to define new
major modes by inheriting key bindings and commands from existing major
modes.

Will Mengarini wrote repeat.el, a command to repeat the preceding
command with its arguments.

Richard Mlynarik wrote cl-indent.el, a package for indenting
Common Lisp code; ebuff-menu.el, an electric browser for
buffer listings; ehelp.el, bindings for browsing help screens;
and rfc822.el, a parser for E-mail addresses in the format
used in mail messages and news articles (Internet RFC 822 and its successors).

Gerd Möllmann was the Emacs maintainer from the beginning of Emacs 21
development until the release of 21.1. He wrote the new display
engine used from Emacs 21 onwards, and the asynchronous timers
facility. He also wrote ebrowse, the C++ browser;
jit-lock.el, the Just-In-Time font-lock support mode;
tooltip.el, a package for displaying tooltips;
authors.el, a package for maintaining the AUTHORS file;
and rx.el, a regular expression constructor.

Stefan Monnier was the Emacs (co-)maintainer from Emacs 23 until
late in the development of 25.1. He added
support for Arch and Subversion to VC, re-wrote much of the Emacs server
to use the built-in networking primitives, and re-wrote the abbrev and
minibuffer completion code for Emacs 23. He also wrote PCL-CVS,
a directory-level front end to the CVS version control system;
reveal.el, a minor mode for automatically revealing invisible
text; smerge-mode.el, a minor mode for resolving diff3
conflicts; diff-mode.el, a mode for viewing and editing context
diffs; css-mode.el for Cascading Style Sheets;
bibtex-style.el for BibTeX Style files; mpc.el, a
client for the Music Player Daemon (MPD); smie.el, a generic
indentation engine; and pcase.el, implementing ML-style pattern
matching. In Emacs 24, he integrated the lexical binding code,
cleaned up the CL namespace (making it acceptable to use CL
functions at runtime), added generalized variables to core Emacs
Lisp, and implemented a new lightweight advice mechanism.

Morioka Tomohiko wrote several packages for MIME support in Gnus and
elsewhere.

Sen Nagata wrote crm.el, a package for reading multiple strings
with completion, and rfc2368.el, support for mailto:
URLs.

Erik Naggum wrote the time-conversion functions. He also wrote
disp-table.el, for dealing with display tables;
mailheader.el, for parsing email headers; and
parse-time.el, for parsing time strings.

Thomas Neumann and Eric Raymond wrote make-mode.el,
a mode for editing makefiles.

Thien-Thi Nguyen and Dan Nicolaescu wrote hideshow.el, a minor
mode for selectively displaying blocks of text.

Dan Nicolaescu added support for running Emacs as a daemon. He also
wrote romanian.el, support for editing Romanian text;
iris-ansi.el, support for running Emacs on SGI's xwsh
and winterm terminal emulators; and vc-dir.el, displaying
the status of version-controlled directories.

Hrvoje Nikšić wrote savehist.el, for saving the minibuffer
history between Emacs sessions.

Jeff Norden wrote kermit.el, a package to help the Kermit
dialup communications program run comfortably in an Emacs shell buffer.

Andrew Norman wrote ange-ftp.el, providing transparent FTP
support.

Kentaro Ohkouchi created the Emacs icons used beginning with Emacs 23.

Christian Ohler wrote ert.el, a library for automated regression
testing.

Alexandre Oliva wrote gnus-mlspl.el, a group params-based mail
splitting mechanism.

Takaaki Ota wrote table.el, a package for creating and editing
embedded text-based tables.

Jens Petersen wrote find-func.el, which makes it easy to find
the source code for an Emacs Lisp function or variable.

Nicolas Petton wrote map.el, a library providing
map-manipulation functions that work on alists, hash-table and arrays;
seq.el, a library providing advanced sequence manipulation
functions and macros; and thunk.el, a library providing
functions and macros to delay the evaluation of forms. He also
created the new icon in Emacs 25.

Daniel also rewrote apropos.el (originally written by Joe Wells),
for finding commands, functions, and variables matching a regular
expression; and, together with Jim Blandy, co-authored wyse50.el,
support for Wyse 50 terminals. He also co-wrote compile.el
(q.v.) and ada-stmt.el.

Christian Plaunt wrote soundex.el, an implementation of the
Soundex algorithm for comparing English words by their pronunciation.

David Ponce wrote recentf.el, a package that puts a menu of
recently visited files in the Emacs menu bar; ruler-mode.el, a
minor mode for displaying a ruler in the header line; and
tree-widget.el, a package to display hierarchical data
structures.

Francesco A. Potortì wrote cmacexp.el, providing a command which
runs the C preprocessor on a region of a file and displays the results.
He also expanded and redesigned the etags program.

Ashwin Ram wrote refer.el, commands to look up references in
bibliography files by keyword.

Eric S. Raymond wrote vc.el, an interface to the RCS and SCCS
source code version control systems, with Paul Eggert; gud.el,
a package for running source-level debuggers like GDB and SDB in
Emacs; asm-mode.el, a mode for editing assembly language code;
AT386.el, terminal support package for IBM's AT keyboards;
cookie1.el, support for fortune-cookie programs like
yow.el and spook.el; finder.el, a package for
finding Emacs Lisp packages by keyword and topic; keyswap.el,
code to swap the <BS> and <DEL> keys; loadhist.el,
functions for loading and unloading Emacs features;
lisp-mnt.el, functions for working with the special headers
used in Emacs Lisp library files; and code to set and make use of the
load-history lisp variable, which records the source file from
which each lisp function loaded into Emacs came.

Holger Schauer wrote fortune.el, a package for using fortune in
message signatures.

William Schelter wrote telnet.el, support for telnet
sessions within Emacs.

Ralph Schleicher wrote battery.el, a package for displaying
laptop computer battery status, and info-look.el, a package for
looking up Info documentation for symbols in the buffer.

Michael Schmidt and Tom Perrine wrote modula2.el, a mode for
editing Modula-2 code, based on work by Mick Jordan and Peter Robinson.

Ronald S. Schnell wrote dunnet.el, a text adventure game.

Philippe Schnoebelen wrote gomoku.el, a Go Moku game played
against Emacs; and mpuz.el, a multiplication puzzle.

Jan Schormann wrote solitaire.el, an implementation of the
Solitaire game.

Alex Schroeder wrote ansi-color.el, a package for translating
ANSI color escape sequences to Emacs faces; sql.el, a package
for interactively running an SQL interpreter in an Emacs buffer;
cus-theme.el, an interface for custom themes; master.el, a
package for making a buffer ‘master’ over another; and
spam-stat.el, for statistical detection of junk email. He also
wrote parts of the IRC client ERC (q.v.).

Randal Schwartz wrote pp.el, a pretty-printer for lisp objects.

Manuel Serrano wrote the Flyspell package, which does spell checking
as you type.

Hovav Shacham wrote windmove.el, a set of commands for selecting
windows based on their geometrical position on the frame.

Stanislav Shalunov wrote uce.el, for responding to unsolicited
commercial email.

Richard Sharman wrote hilit-chg.el, which uses colors to show
recent editing changes.

Lynn Slater wrote help-macro.el, a macro for writing interactive
help for key bindings.

Chris Smith wrote icon.el, a mode for editing Icon code.

David Smith wrote ielm.el, a mode for interacting with the Emacs
Lisp interpreter as a subprocess.

Paul D. Smith wrote snmp-mode.el.

William Sommerfeld wrote scribe.el, a mode for editing Scribe
files, and server.el, a package allowing programs to send files
to an extant Emacs job to be edited.

Andre Spiegel made many contributions to the Emacs Version Control
package, and in particular made it support multiple back ends.

Michael Staats wrote pc-select.el, which rebinds keys for
selecting regions to follow many other systems.

Richard Stallman invented Emacs. He is the original author of GNU
Emacs, and has been Emacs maintainer over several non-contiguous
periods. In addition to much of the core Emacs code, he has
written easymenu.el, a facility for defining Emacs menus;
image-mode.el, support for visiting image files;
menu-bar.el, the Emacs menu bar support code;
paren.el, a package to make matching parentheses stand out in
color; and also co-authored portions of CC mode.

Sam Steingold wrote midnight.el, a package for running a
command every midnight.

Ake Stenhoff and Lars Lindberg wrote imenu.el, a framework for
browsing indices made from buffer contents.

Peter Stephenson wrote vcursor.el, which implements a virtual
cursor that you can move with the keyboard and use for copying text.

Ken Stevens wrote ispell.el, a spell-checker interface.

Kim F. Storm made many improvements to the Emacs display engine,
process support, and networking support. He also wrote
bindat.el, a package for encoding and decoding binary data;
CUA mode, which allows Emacs to emulate the standard CUA key
bindings; ido.el, a package for selecting buffers and files
quickly; keypad.el for simplified keypad bindings; and
kmacro.el, the keyboard macro facility.

Steve Strassmann did not write spook.el, and even if he did, he
really didn't mean for you to use it in an anarchistic way.

Olaf Sylvester wrote bs.el, a package for manipulating Emacs
buffers.

Tibor Šimko and Milan Zamazal wrote slovak.el, support for
editing text in Slovak language.

Luc Teirlinck wrote help-at-pt.el, providing local help through
the keyboard.

Jean-Philippe Theberge wrote thumbs.el, a package for viewing
image files as thumbnails.

Spencer Thomas wrote the original dabbrev.el, providing a command
which completes the partial word before point, based on other nearby
words for which it is a prefix. He also wrote the original dumping
support.

Toru Tomabechi contributed to Tibetan support.

Markus Triska wrote linum.el, a minor mode that displays line
numbers in the left margin.

Tom Tromey and Chris Lindblad wrote tcl.el, a mode for editing
Tcl/Tk source files and running a Tcl interpreter as an Emacs
subprocess. Tom Tromey also wrote bug-reference.el, providing
clickable links to bug reports; and the first version of the Emacs
package system.

Eli Tziperman wrote rmail-spam-filter.el, a spam filter for RMAIL.

Daiki Ueno wrote starttls.el, support for Transport Layer
Security protocol; sasl-cram.el and sasl-digest.el (with
Kenichi Okada), and sasl.el, support for Simple Authentication
and Security Layer (SASL); plstore.el for secure storage of
property lists; and the EasyPG (and its predecessor PGG)
package, for GnuPG and PGP support.

Masanobu Umeda wrote GNUS, a feature-rich reader for Usenet news that
was the ancestor of the current Gnus package. He also wrote
rmailsort.el, a package for sorting messages in RMAIL folders;
metamail.el, an interface to the Metamail program;
gnus-kill.el, the Kill File mode for Gnus; gnus-mh.el, an
mh-e interface for Gnus; gnus-msg.el, a mail and post interface
for Gnus; and timezone.el, providing functions for dealing with
time zones.

Neil W. Van Dyke wrote webjump.el, a Web hotlist package.

Didier Verna wrote rect.el, a package of functions for
operations on rectangle regions of text. He also contributed to Gnus
(q.v.).

Joakim Verona implemented ImageMagick support.

Ulrik Vieth implemented meta-mode.el, for editing MetaFont code.

Geoffrey Voelker wrote the Windows NT support. He also wrote
dos-w32.el, functions shared by the MS-DOS and MS-Windows ports
of Emacs, and w32-fns.el, MS-Windows specific support functions.

Johan Vromans wrote forms.el and its associated files, a mode for
filling in forms. He also wrote iso-acc.el, a minor mode
providing electric accent keys.

Colin Walters wrote Ibuffer, an enhanced buffer menu.

Barry Warsaw wrote cc-mode.el, a mode for editing C, C++,
and Java code, based on earlier work by Dave Detlefs, Stewart Clamen,
and Richard Stallman; elp.el, a profiler for Emacs Lisp
programs; man.el, a mode for reading Unix manual pages;
regi.el, providing an AWK-like functionality for use in lisp
programs; reporter.el, providing customizable bug reporting for
lisp packages; and supercite.el, a minor mode for quoting
sections of mail messages and news articles.

Christoph Wedler wrote antlr-mode.el, a major mode for ANTLR
grammar files.

Morten Welinder helped port Emacs to MS-DOS, and introduced face
support into the MS-DOS port of Emacs. He also wrote
desktop.el, facilities for saving some of Emacs's state between
sessions; timer.el, the Emacs facility to run commands at a
given time or frequency, or when Emacs is idle, and its C-level
support code; pc-win.el, the MS-DOS “window-system” support;
internal.el, an “internal terminal” emulator for the MS-DOS
port of Emacs; arc-mode.el, the mode for editing compressed
archives; s-region.el, commands for setting the region using
the shift key and motion commands; and dos-fns.el, functions
for use under MS-DOS.

Joe Wells wrote the original version of apropos.el (q.v.);
resume.el, support for processing command-line arguments after
resuming a suspended Emacs job; and mail-extr.el, a package for
extracting names and addresses from mail headers, with contributions
from Jamie Zawinski.

Rodney Whitby and Reto Zimmermann wrote vhdl-mode.el, a major
mode for editing VHDL source code.

John Wiegley was the Emacs maintainer from Emacs 25 onwards. He wrote
align.el, a set of commands for aligning text according to
regular-expression based rules; isearchb.el for fast buffer
switching; timeclock.el, a package for keeping track of time
spent on projects; the Bahá'í calendar support; pcomplete.el, a
programmable completion facility; remember.el, a mode for
jotting down things to remember; eudcb-mab.el, an address book
backend for the Emacs Unified Directory Client; and eshell, a
command shell implemented entirely in Emacs Lisp. He also contributed
to Org mode (q.v.).

Mike Williams wrote thingatpt.el, a library of functions for
finding the “thing” (word, line, s-expression) at point.

Roland Winkler wrote proced.el, a system process editor.

Bill Wohler wrote MH-E, the Emacs interface to the MH mail system;
making use of earlier work by James R. Larus. Satyaki Das, Peter S.
Galbraith, Stephen Gildea, and Jeffrey C. Honig also wrote various
MH-E components.

Dale R. Worley wrote emerge.el, a package for interactively
merging two versions of a file.

Francis J. Wright wrote woman.el, a package for browsing
manual pages without the man command.

Jonathan Yavner wrote testcover.el, a package for keeping track
of the testing status of Emacs Lisp code; unsafep.el to determine
if a Lisp form is safe; and the SES spreadsheet package.

Ryan Yeske wrote rcirc.el a simple Internet Relay Chat client.

Ilya Zakharevich and Bob Olson wrote cperl-mode.el, a major
mode for editing Perl code. Ilya Zakharevich also wrote
tmm.el, a mode for accessing the Emacs menu bar on a text-mode
terminal.

Milan Zamazal wrote czech.el, support for editing Czech text;
glasses.el, a package for easier reading of source code that
uses illegible identifier names; and tildify.el, commands for
adding hard spaces to text, TeX, and SGML/HTML files.

Victor Zandy wrote zone.el, a package for people who like to
zone out in front of Emacs.

Eli Zaretskii made many standard Emacs features work on MS-DOS and
Microsoft Windows. He also wrote tty-colors.el, which
implements transparent mapping of X colors to tty colors; and
rxvt.el. He implemented support for bidirectional text, menus
on text-mode terminals, and built-in display of line numbers.

Jamie Zawinski wrote much of the support for faces and X selections.
With Hallvard Furuseth, he wrote the optimizing byte compiler used
from Emacs 19 onwards. He also wrote mailabbrev.el, a package
that provides automatic expansion of mail aliases, and
tar-mode.el, which provides simple viewing and editing commands
for tar files.

Andrew Zhilin created the Emacs 22 icons.

Shenghuo Zhu wrote binhex.el, a package for reading and writing
binhex files; mm-partial.el, message/partial support for MIME
messages; rfc1843.el, an HZ decoding package;
uudecode.el, an Emacs Lisp decoder for uuencoded data; and
webmail.el, an interface to Web mail. He also wrote several
other Gnus components.

Ian T. Zimmerman wrote gametree.el.

Reto Zimmermann wrote vera-mode.el.

Neal Ziring and Felix S. T. Wu wrote vi.el, an emulation of the
VI text editor.

Ted Zlatanov (as well as his contributions to the Gnus newsreader)
wrote an interface to the GnuTLS library, for secure network
connections; and a futures facility for the URL library.

Detlev Zundel wrote re-builder.el, a package for building regexps
with visual feedback.